INSTEAD of eating less and exercising more, it appears the UK’s huge obese population is doing just the opposite.

The number of obese people in this country has more than doubled over the last 20 years, and the Organisation for Economic Co-operation and Development (OECD) estimates a quarter of adults are now obese.

Far from heeding the warnings about obesity-related illnesses such as heart disease, cancer and type II diabetes, Brits are still piling on the pounds, and the ill health they suffer as a result is costing the NHS £4.4bn a year.

In the run-up to National Obesity Week, which takes place between January 23 and 30, the National Obesity Forum (NOF) stresses it hasn’t given up hope that its ‘eat healthy, exercise more’ message will be taken on board by more people.

But it’s using the week to highlight the efforts of some food manufacturers to make their products more healthy – and hoping that the rest of the industry will quickly follow suit.

Tam Fry, spokesperson for the NOF, says that over the last 10 years, the organisation has been very critical of companies producing food and drink containing high levels of ingredients critical in the development of obesity.

But he admits that since about 2002, many companies have started to recalculate the levels of fat, salt and sugar in their products.

The changes have taken a long time, he says, because manufacturers have to “re-educate” their customers into liking their healthier goods.

He said: “It’s now becoming apparent that this strategy’s working, and we feel the time’s right for us to re-evaluate our criticism, and acknowledge those companies we feel have made huge advances in reformulating their products, meaning there are less calories in each item.

“That has to be hugely welcomed.”

Mr Fry mentions Walkers crisps, which has taken a large amount of salt out of products; McVities, which has taken “huge amounts” of sugar out of its cakes and confectionary; Kelloggs, which is reducing sugar content; and Coca Cola, which introduced two low-calorie versions, Diet Coke and Coke Zero.

“People are totally responsible for what they consume, and there’s no way anyone can change that,” he explained.

“But what we hope is that by underlining the fact that they’ve got choices, we’re helping people choose a healthier way of life.”

He says people are becoming very health conscious, and companies are making changes as a result.

“Every food producer has seen the writing on the wall – if they don’t do something, they won’t carry public opinion,” he said.

“They’ve realised there are huge profits to be made from manufacturing healthy food.”

Mr Fry says introducing a so-called ‘fat tax’, where unhealthy, non-essential food is taxed, could be another major help in beating the UK’s obesity problem.

The idea is that hitting people in the pocket will make them eat less junk food, in the same way that taxes on tobacco work.

“Indulgence food and treats high in sugar aren’t essential for life, and by increasing the price of the treats through tax, you’ve got a stark reminder that this isn’t terrific for you,” said Mr Fry.

“The money made from the taxes could then go towards subsidising healthy products like fruit and vegetables, bringing the price down.

“It’s all part of a balancing act to try and change people’s behaviour into healthier eating. We’re trying to remove calories, by the millions, from the food chain.”

He says behaviour change will be hugely improved if it’s tied to real money, explaining: “You’d pay more for your chocolate, and less for your fruit and vegetables. That’s absolutely ideal.”

Such legislation would be “hugely unpopular”, he admits, but points out that in 2007, it was estimated that unless there was dramatic change, obesity would cost £50bn by 2050.

Other countries, such as Denmark and Portugal, already have a ‘fat tax’, and Mr Fry added: “The Government really should consider such options as part of the armoury against obesity. The enormity of the problem is such that it’s got to happen sooner rather than later.”

Not surprisingly, the Food and Drink Federation (FDF), which represents the UK’s food and non-alcoholic drink manufacturers, completely disagrees with the introduction of this tax.

Julian Hunt, the FDF’s spokesperson, said: “We haven’t seen any evidence to show such a tax will make anybody any lighter. It would just be another tax on consumers to provide money for the Treasury.”

He stresses that 20% VAT is already payable on soft drinks, snacks and chocolate, and points out that, unlike heavily-taxed cigarettes, most people don’t eat several bars of chocolate every day.

“People won’t stop buying chocolate to buy more bananas. It’s just not going to happen,” he said.

What has already happened, he adds, is that the food and drink industry has responded well to public health pressures, with many companies looking at changing the recipes of products to make them healthier.

Pointing out that two thirds of soft drinks are now low-calorie or no added sugar, he said: “It’s a sign of innovation.”

Mr Hunt insists that although there’s consumer demand for healthier products, manufacturers are also changing them because “It’s the right thing to do”.

He said: “There are real concerns about how waistlines are getting bigger in the UK, and a genuine recognition that there are real issues that need to be addressed.”

But a key motivation is, of course, consumer demand.

“There’s an appetite among consumers for products that are healthier,” Mr Hunt added. “If you want to be competitive and successful as a company, you’ve got to respond.”

Huge amounts of money are being invested to create new, healthier products.

McVities, for instance, spent £6m changing ingredients and revamping its factory in order to produce healthier biscuits.